I was just curious, I've seen a number of cases where the initial dominant type of dino was taken care of only to have another type show up. But also with the encysting dinos seen the same kind come back months later.I have not verified them yet. i plan to do that today. at this point im only assuming it is ostreopsis because that was what i battled last time.
I ran my UV for 2-months before pulling both the sand and UV out of my system.
I can't really comment on if and how much a UV is detrimental to the platonic life in a reef tank. I personally run my UV continuously. I did shut it off for a few weeks after running it for about 2 months but started seeing a few Coolia back in my system so turned it back on. I attribute it to encysted dinos "hatching" as I have found a number of encysted dinos. With dino cysts being able to hang out for many months I feel it is worth running UV long enough for any cysts to "hatch"